FUNCTIONAL BLOCK LEVEL THERMAL CONTROL

1 . An integrated circuit comprising:

a plurality of functional units, wherein each of the plurality of functional units is implemented on a die of the integrated circuit, and wherein each of the functional units includes one or more temperature sensors; and

a temperature control unit coupled to each of the functional units, wherein the temperature control unit is configured to monitor a temperature of each of the plurality of functional units based on temperature information provided from the temperature sensors;

wherein, if the temperature exceeds a first threshold value for a particular one of the plurality of functional units, the temperature control unit is configured to perform a first temperature control action on the particular one of the plurality of functional units independently of other ones of the plurality of functional units.

2 . The integrated circuit as recited in claim 1 , wherein each of the plurality of functional units is configured to receive a corresponding one of a plurality of clock signals, and wherein the first temperature control action comprises reducing a frequency of the clock signal corresponding to the particular one of the plurality of functional units.

3 . The integrated circuit as recited in claim 1 , wherein each of the plurality of functional units is coupled to a corresponding one of a plurality of voltage planes, and wherein the first temperature control action comprises reducing a voltage present on the voltage plane corresponding to the particular one of the plurality of functional units.

4 . The integrated circuit as recited in claim 3 , wherein the first temperature control action comprises removing power from the particular one of the plurality of functional units.

5 . The integrated circuit as recited in claim 1 , wherein the integrated circuit is a processor, and wherein the plurality of functional units includes one or more of the following: one or more processor cores, a memory controller hub, a graphics processor.

6 . The integrated circuit as recited in claim 5 , wherein the temperatures control action comprises re-allocating a portion of a processing task from a first one of the processor cores to a second one of the processor cores.

7 . The integrated circuit as recited in claim 1 , wherein one or more of the functional units includes a plurality of temperature sensors coupled to a filter, wherein the filter is configured to provide a maximum temperature to the temperature control unit from among the plurality of temperature sensors of the functional unit.

8 . The integrated circuit as recited in claim 1 , wherein the temperature control unit is configured to perform a second temperature control action if the temperature of the particular one of the plurality of functional units continues to exceed the first threshold value for a predetermined time after the first temperature control action.

9 . The integrated circuit as recited in claim 1 , wherein the temperature control unit is configured to perform a second temperature control action if the temperature of the particular one of the plurality of functional units falls below a second threshold value.

10 . The integrated circuit as recited in claim 9 , wherein the temperature control unit is configured to perform a third temperature control action whenever the temperature of the particular one of the plurality of functional units crosses a third threshold value, wherein the third threshold value is between the first threshold value and the second threshold value.

11 . A method comprising:

receiving temperature readings from each of a plurality of functional units implemented on an integrated circuit die;

determining if a temperature reading from any of the plurality of functional units exceeds a first threshold value; and

if the temperature exceeds the first threshold value for a particular one of the plurality of functional units, performing a first temperature control action on the particular one of the plurality of functional units independently of other ones of the plurality of functional units.

12 . The method as recited in claim 11 , wherein the first temperature control action comprises reducing a frequency of a clock signal provided to the particular one of the plurality of functional units independently of a frequency of corresponding clock signals provided to other ones of the plurality of functional units.

13 . The method as recited in claim 11 , wherein the first temperature control action comprises reducing a voltage on a voltage plane coupled to the particular one of the plurality of functional units independent of a voltage of voltage planes coupled to other ones of the plurality of functional units.

14 . The method as recited in claim 13 , wherein the first temperature control action comprises removing power from the particular one of the plurality of functional units.

15 . The method as recited in claim 11 , wherein the integrated circuit is a processor having at least a first processor core and a second processor core, and wherein the first temperature control action comprises re-allocating a portion of a processing task from the first processor core to the second processor core.

16 . The method as recited in claim 11 , further comprising:

performing a second temperature control action if the temperature of the particular one of the plurality of functional units continues to exceed the first threshold value for a predetermined time after the first temperature control action;

performing a third temperature control action if the temperature of the particular one of the plurality of functional units falls below a second threshold value; and

performing a fourth temperature control action whenever the temperature of the particular one of the plurality of functional units crosses a third threshold value, wherein the third threshold value is between the first threshold value and the second threshold value.

17 . A processor comprising:

a plurality of functional units, the plurality of functional units including a first processor core, a second processor core, and a northbridge unit; and

a temperature control unit, wherein the temperature control unit is coupled to receive readings indicative of a temperature of each of the plurality of functional units; and

wherein, if the temperature exceeds a first threshold value for a particular one of the plurality of functional units, the temperature control unit is configured to perform a first temperature control action on the particular one of the plurality of functional units independently of other ones of the plurality of functional units.

18 . The processor as recited in claim 17 , wherein the first temperature control action comprises reducing a frequency of a clock signal provided to the particular one of the plurality of functional units independently of a frequency of corresponding clock signals provided to other ones of the plurality of functional units.

19 . The processor as recited in claim 17 , wherein the first temperature control action comprises reducing a voltage on a voltage plane coupled to the particular one of the plurality of functional units independent of a voltage of voltage planes coupled to other ones of the plurality of functional units.

20 . The processor as recited in claim 17 , wherein the first temperature control action comprises re-allocating a portion of a processing task from the first processor core to the second processor core.